Vehicle AC Refrigerant Leak Detection Without Extra Sensors
Solution Overview
Problem
Existing vehicle air conditioning systems that use flammable refrigerants face challenges in detecting leaks without the need for additional sensors, which increases costs and requires installation space.
Innovation Solution
A vehicle air conditioning system that calculates refrigerant density based on outside air temperature and pressure, determining if it falls below a threshold value, thereby detecting potential leaks without separate sensors, and includes a notification system to alert users of impending explosion risks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a separate flammable refrigerant detection sensor is provided to detect leakage, then detection capability is improved, but device complexity and cost increase
Solution Approach 1:
The control device performs multiple functions: it controls the air conditioning system operation, monitors refrigerant density by calculating from temperature and pressure data, and detects potential leakage risks. By making the control device multi-functional, the patent eliminates the need for separate detection sensors, reducing device complexity and cost while maintaining detection capability
Solution Approach 2:
The control device uses its own existing sensors (temperature and pressure sensors already present in the system) to calculate refrigerant density and detect leakage risks. The system serves itself by utilizing existing resources rather than requiring additional dedicated detection equipment, thereby reducing complexity and installation requirements
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach allows for safe detection of flammable refrigerant leaks without additional sensors, reducing costs and ensuring safety against explosions by disabling door opening and issuing warnings when the refrigerant density approaches the explosion limit.
Implementation Method 1
a control device that calculates a refrigerant density as a density of the refrigerant based on the outside air temperature and the pressure
Data Source
AI summary
The purpose of the present invention is to provide a vehicle air conditioning system and a control method of the vehicle air conditioning system which enable detecting leaks of flammable refrigerant without requiring a separate sensor. This vehicle air conditioning system is provided with: a refrigeration cycle for cooling (23); a heat pump cycle for heating (33); a refrigerant that is very flammable, has an explosive range near room temperature, and circulates in the refrigeration cycle for cooling (23) and the heat pump cycle for heating (33); an outside temperature sensor (44) which detects the outside temperature; a pressure sensor (49) which detects the refrigerant pressure; and a control device which calculates the refrigerant density, which is the density of refrigerant, on the basis of the outside temperature and the pressure, and determines whether or not the refrigerant density has fallen below a prescribed threshold value which is based on the amount of sealed refrigerant, the total volume in the refrigeration cycle for cooling (23) and in the heat pump cycle for heating (33), the volume of the vehicle cabin, the standard density of the atmosphere, and the explosive limit of the refrigerant.